Yes, I do get a sense that the "living world" ethos involves deliberately eschewing any sort of pathos or emotional dimension to play.On Plausibility:
What I would say looking at my own GMing and self-scouting I have done after the fact is that I find say running Stars Without Number to the instructions it provides (and referencing blorb principles) to the best of my ability that I am still making aesthetic decisions that fit within my sense of what is plausible because when you have to create or design things there will be creative decisions. I would say that I am much more focused on plausibility as a constraint than I would be in say something like Dune 2d20. I would assume Stars Without Number as described in its text would count as a Living World Sandbox.
I have also seen a fair number of posts from Living World where they discuss certain aesthetic subjects they avoid (interpersonal drama. introspection, et al). That seems to imply within the context of the what's plausible decision space is also a filter based on aesthetic priorities.
In my BW play, as I described not too far upthread, plausibility is an obvious consideration. But it's not the only one. I mean, what is the likelihood that getting lost in the catacombs would leave you beneath a grate where you just happen to see the now-woken Halika, who looks down and gloats at you, confident she can get to the tower first? It's possible, but it's certainly not the most likely thing.
But it's what I went for, as it seemed to me to be a good fit with the other principles that governed my decision.